The present invention relates to an edible plastified dispersion having a fat content of less than 30% by weight and comprising a continuous fat phase, which includes an aqueous phase that contains protein or hydrocolloid or a mixture thereof.
Edible, plastified fat-continuous dispersions (often called spreads) that can be used as replacement for butter or margarine, having a fat content below 80 wt. %, are well known. A wide variety of such products is commercially available. Most of these products have a fat content of about 40 wt. %. There is, however, need of spreads having a fat content of substantially less than 40 wt. %.
A spread should have a plastified continuous fat phase to give it suitable spreadability. It should not release moisture when it is being spread. Furthermore, a spread should be spreadable at refrigerator temperature, be stable at room temperature, but destabilize and release its flavour in the mouth. These goals are very difficult to achieve if only a small amount of fat is to be used to constitute a continuous phase.
In GB 2,035,360 a process is disclosed for the preparation of spreads containing 20 wt. % fat. According to this process, the aqueous phase is sprayed onto the fatty phase. During the addition of the sprayed aqueous phase, the emulsion is circulated through a static mixer to increase the viscosity. The final viscosity suitably is about 18000 cps (18000 mPa.s) at a shear rate of 13 sec..sup.-1 and 2700 cps (2700 mPa.s) at a shear rate of 134 sec..sup.-1 at 38.degree. C. When this viscosity has been obtained, the emulsion is cooled and worked to cause crystallization of fat to occur. In practice, this process has not been successful. It is difficult to apply the process under factory conditions.
EP 0 011 344 describes the incorporation in fat-continuous spreads containing 18-82 wt. % fat phase, of a gelled aqueous phase having a softening point of at least 33.degree. C., showing a sharp decrease in gel strength at a temperature ranging from 45.degree. to 70.degree. C. and a gel strength at a temperature below the softening point ranging from 0.1 to 30 N/cm.sup.2. Spreads having a very low fat content, prepared with aqueous phase compositions as disclosed in EP 0 011 344 have been found to be unsatisfactory. In particular, such spreads tend to release water under spreading conditions.
U.S. Pat. No. 4,536,408 describes low-fat spreads comprising 15-35 wt. % fat and 15-35 wt. % of a non-gelling starch hydrolysate having a DE (dextrose equivalent) of 4-25. The products are prepared by cooling and mixing the fat into an aqueous solution of the starch hydrolysate with a high-speed blender until phase inversion occurs. The products disclosed in U.S. Pat. No. 4,536,408 have been found to have a poor oral response. They do not break down sufficiently in the mouth and, consequently, they have a poor flavour release.
The process employed to produce the spreads according to U.S. Pat. No. 4,536,408 involves phase inversion of an oil-in-water emulsion containing a fat blend having a melting point above about 38.degree. C., with a high-speed blender. Substantial problems would be encountered if one were to try to carry out such a process, requiring the application of very high shear forces, on a factory scale.
Another disadvantage of the products according to the proposal of U.S. Pat. No. 4,536,408 is that they contain a very substantial amount of carbohydrate. Although the fat content of the products is low, the reduction in calorific value by reducing the fat content is partially offset by incorporating the starch hydrolysate.